By the time he realizes he _____ a mistake, it’ll be too late for him to change his mind.
| A．makes | B．made | C．has made | D．had made |
The flu is believed by viruses that like to reproduce in the cells inside the human nose and throat.
| A．causing | B．being caused | C．to be caused | D．to have caused |
His mother suggested he ______ to see the doctor, because his pale face suggested he ____ ill.
| A．would go, had been | B．go, was | C．went, had been | D．must go, was |
What I need is _____ book that contains ______ ABC of oil painting.
| A．a; 不填 | B．the; 不填 | C．the; an | D．a; the |
What a pity! I missed meeting my boss at the airport because my car was ______ in the traffic jam.
| A．broken up | B．kept away | C．held up | D．kept up |
His physical disability makes _____ rather difficult for him to find a good job.
| A．him | B．that | C．this | D．it |